Table of Contents
Advertisement
Sample Program
Program Listing
'--- Set up linkage to spectrum analyzer and initialize
'--- Initialize the analyzer
CALL GPIB.CONTROLLER(3)
'--- Set Center Frequency
'--- Set Span
'--- Set Reference Level
'--- Set Resolution Bandwidth
'--- Adjust Preselector to proper band
2706 RF Preselector
The following is a typical program you can use to automatically control your
Preselector. This program instructs the Preselector and a Tektronix 271X-Series
GPIB compatible spectrum analyzer to scan 40 MHz to 100 MHz, then 150 MHz
to 200 MHz. It first selects a Preselector filter, then instructs the spectrum
analyzer to scan that frequency range. This operation can be repeated for all eight
Preselector filters.
NOTE. You must correct for the different losses in Preselector filters when you
switch between filters. For example, if you switch from band 7 (nominal loss:
2.0 dB, ±1.0 dB) to band 8 (nominal loss: 4.0 dB, ±1.0 dB) you must increase the
spectrum analyzer's gain by 2.0 dB in the INSERT.LOSS subroutine at the end of
the following program.
DEVICE$ = "TEK_SA"
CALL GPIB.CONTROLLER(1) ' identify the device
CALL GPIB.CONTROLLER(7) ' force timeout to 30 seconds
wrt$ = "MXHLD OFF;GRAT ON;REDOUT ON;TRIG FRERUN;VRT LOG:10;VIDFLT
OFF;VIEW A:OFF,B:ON,C:OFF,D:ON;SAVE A:OFF,B:OFF,C:OFF;"
wrt$ = "FRE 70 MHZ"
CALL GPIB.CONTROLLER(3)
wrt$ = "SPA 6 MHZ"
CALL GPIB.CONTROLLER(3)
wrt$ = "REF - 20"
CALL GPIB.CONTROLLER(3)
wrt$ = "RES 120 KHZ"
CALL GPIB.CONTROLLER(3)
DEVICE$ = "PRE_SEL"
CALL GPIB.CONTROLLER(1)
wrt$ = "B4"
CALL GPIB.CONTROLLER(3)
DEVICE$ = "TEK_SA"
CALL GPIB.CONTROLLER(1)
Appendix B: Using the GPIB Interface
'set PRESELECTOR for 30 MHz to 125 MHz
're - address analyzer
B–3
Advertisement
Table of Contents
